Caleb Wells was sitting down. He felt like cursing the knees that had been weak ever since the unseen speakers revealed themselves to him. He wasn't afraid of the turtles; at least, he didn't think he was. Right now he was experiencing a curious sensation that hovered between shock and fascination. He finally braced both hands on the arms of the desk chair, and slowly got to his feet.

"Are you all right, Caleb?" Luke was the first to ask.

"Yes, I'm fine. Is it okay if I approach them?"

The blond man appeared to be repressing a smile. "You can even talk to them directly if you want to."

Caleb turned to gaze at the strangers unabashedly, not bothering to hide his interest. "Forgive me, I'm not usually at a loss for words, but I'm feeling a little overwhelmed," he admitted. "Who are you? What do you have to do with Luke?" Caleb looked back at the younger man, inviting him to answer the questions too.

"We'll be happy to fill in all the blanks," the blue-masked turtle said evenly. "But we shouldn't linger here. We're seriously pushing our luck."

Caleb nodded. "That's true. We're taking an awful risk, the longer we stay here. How can you...will you be..."

"We'll get out the same way we came in," the purple-masked turtle volunteered. "We'll meet you back at the van, Doc."

"And all of you can meet me back at my house," Caleb said firmly, fixing Luke with a serious look. "You will meet me back at the house, won't you?"

Luke nodded meekly. "On my honor, Caleb. We'll be over there right away."

Caleb still felt a little shaky as he crossed through the parking lot, and he had a hard time keeping his farewell to the security guards completely casual. He was about to climb into his car when he heard footsteps quickly approaching. He looked over his shoulder, and saw Luke coming toward him.

"What's going on?" Caleb was immediately tense, though he wasn't sure why.

"I thought I might ride with you," Luke replied. "Greg knows the way to your house from here."

Caleb gazed at the younger man silently for a few seconds, confusion and hurt still twisting through his gut. None of the circumstances surrounding the so called "break-in" at the Lab had been explained yet. He'd barely had the chance to get over the surprise of meeting Luke's unique companions before they'd decided to move.

"I thought I might get a chance to talk to you alone, and try to clear some of this up," Luke said carefully.

"That would be the least you could do," Caleb answered stiffly.

He unlocked the doors from the driver's side, and motioned for Luke to get in. "We've only got about fifteen minutes, so I hope you can talk fast."

Luke looked at him tentatively. "Where do you want me to start? Would you rather hear the basics about why we came, or do you want information about my friends?"

"I think I can take my time getting acquainted with your...friends in a little while. Why don't you just tell me what this raid was all about?"

The younger man took a deep breath. "I'll do my best to explain, but I have to lay some groundwork for you. Surely you understand that the turtles' mutation isn't, um...naturally occurring. It was caused by a chemical reaction that permanently transformed their DNA, and gave them their humanoid abilities. Unfortunately, we've discovered that the mutation wasn't entirely beneficial."

"Very few of them are, you know."

"So I've heard. In any case, we discovered a specific genetic defect years ago, when their father became ill."

"They have a father?"

"His mutation was different from theirs, but they shared a similar genetic structure-"

"What about this defect?" Caleb interrupted. "Does it have something to do with your trip down here tonight?"

Luke nodded.

"Is this a matter of curiosity, or is it relating to their father being sick?"

"He already died," Luke said bleakly. "His lungs failed because of a condition relating to the defect. The lung stem cells began mutating spontaneously, and attacking the surface walls of the alveoli. There was so much tissue damage that the exchange of oxygen and carbon dioxide was cut off."

Caleb had to force himself to pay attention to the road, but his ears were sharply attuned to Luke. "Okay, so their father died. What does that have to do with tonight?"

"The genetic defect that caused his death wasn't unique to their father. All four of the turtles possess the unstable stem cell, which we now realize has the potential to develop into this condition inside every single one of them. One of the brothers is sick. It's been going on for months, and we couldn't determine the true source of it. We never compared his illness to his father's, because Mike's trouble started out differently than Splinter's did. In their father's case it was a consistent downhill trend, whereas Mike had an up and down battle where he would improve for days at a time, only to get sick again. We were distracted by a couple of different factors, and missed the signs that were right in front of us.

"We performed a lung biopsy on Mike a couple of days ago, and discovered the same type of damaged lung tissue that Splinter had. He's gotten worse over the last couple of weeks, and I don't think it's going to let up this time. Mike will die if we don't intervene somehow...and the rest of them will probably follow at some point," Luke said tightly.

Caleb drummed his fingers against the steering wheel. "So, since you're dealing with a genetic defect, you thought you'd fight stem cells with stem cells."

Luke nodded. "We know that healthy stem cells can possibly reverse the tissue damage, as well as overcome the mutated cells-"

"But it would take a number in excess of millions of cells to achieve that kind of success, if it could be attained at all. I'm guessing you already know that."

The younger man took a shaky breath. "We know that the chances of saving him at this point aren't very good, but we've never given up without a fight before...Except in Splinter's case, when he told us to."

Caleb took advantage of a red light by gazing over at Luke. "Is it very advanced? How long do you think he has if you do nothing?"

"We're not doing nothing; he's receiving breathing treatments, which will serve to prolong him."

"For how long?" Caleb asked bluntly.

"I can't say for certain."

Caleb gave him a stern look. "The move you made tonight felt like it was out of sheer desperation, Luke. Telling me how long you think he has left won't make him die any faster."

He didn't answer, and Caleb was on the verge of getting truly irritated, until he noticed the younger man tremble out of the corner of his eye.

"Luke?"

The man wouldn't look at him, instead gazing steadfastly out the window.

"Luke. Talk to me."

The young man shook his head before resting it against the window on the passenger door. "Four months," he said softly. "That's what we've calculated, based on the rate of destruction of his lung tissue. The condition took longer to become acute in Mike, but now that it's exhausted him...the cells are mutating at a faster rate than they did with Splinter."

For a moment Luke sounded unemotional and professional, as he applied the correct physician's tone for delivering a prognosis. The way his body shuddered following the announcement revealed his true feelings on the matter. Caleb pulled over to the shoulder of the road, so that he could focus on the man completely.

"Luke..." Caleb trailed off as the younger man disintegrated before his eyes. The sight of Luke's tears was sobering, and Caleb suddenly found himself thinking of the new strangers less like fascinating oddities, and more like rational living things.

"We need to go," Luke wavered as he collected himself. "They're going to be waiting on us."

"Luke, you are in no position to treat your friends impartially."

"It doesn't matter what I'm in the position to do. We don't have a choice, Caleb. Marcus, Donny, me...that's it. There isn't anyone else."

"What were you going to try to do on your own? Did you come here just to collect research, to learn what you needed to know? Did it even occur to you to come to me?"

"I'm sorry, but you don't know what it means to live like this. I've had over a decade of knowing them, protecting them and being protected by them. Involving other people isn't easy. They saved my life, Caleb. I was in a sad state after I lost my parents. I don't know where I'd be right now if I hadn't been introduced to them because of another medical emergency."

"But you could tell Marcus about them?"

"Marc broke into my apartment and stumbled onto one of them who was there, injured. I didn't introduce them, technically speaking. Marcus snuck in through the figurative back door."

"Do you wish that he hadn't?"

"I'm eternally grateful that Marcus has been there with us. His orthopedic expertise has been invaluable to the turtles, and he's a fantastic friend..." Luke looked at the road ahead of them. "We really should get going."

"Why didn't you want me to know?"

"It's the unknown factor, Caleb. I couldn't be sure of how you'd respond to them. Right now, more than ever, we're in no position to run away."

"Do you honestly believe I'd betray you?" Caleb asked quietly.

"I don't mean any offense by this, but I don't know you well, Caleb. That's just a fact. These guys are my life. I have a wife and a baby, but the turtles are as much my family as Kat and Reina are."

"Then to recap, you got into the Lab tonight, somehow, because you thought you could obtain the research you need to save your sick friend."

"That's it in a nutshell."

"It sounds a lot more complicated than coming to me would have been."

"I know that, Caleb." Luke looked him squarely in the eyes. "We made mistakes, and I can admit that. The truth is, even if we'd gotten away scot free, I doubt that we could have blundered our way through your research in time to find a solution for Mike."

"In other words, you're admitting you need my help."

"To put it mildly, and it's not easy to ask for it. At the same time, I would do anything to help Mike."

"Are you asking for my help, Luke? Are you able to trust me with something like this?"

Luke swallowed deeply. "It isn't that I don't trust you, Caleb. When you get mixed up with our group, everything becomes more complicated. But Donny was right. I don't think we're capable of doing this without some degree of help from you."

"Some degree? What on earth does that mean, Luke?"

"I'm trying not to make any assumptions here, Caleb. This could end up being a huge distraction if you allow it to."

Caleb gripped the steering wheel between his fingers in frustration. "Luke, you have to tell me what you're really thinking. Are you concerned about derailing my research, or are you incapable of trusting me with the weight of this secret?"

"I don't want to ask you to give up your life," Luke said quickly. "We just blew into town, and you don't know the turtles from Adam. You didn't ask for any of this."

Caleb sighed inwardly. We're not going anywhere fast. It's obvious that he doesn't want me this close to his special friends.

"Maybe we could start this a little slower?" Caleb suggested. "I don't know anything about them yet, except that they're masters of breaking and entering without looking like they're doing it."

Luke glanced down, and then made eye contact with him again. "Would you be willing to come with us to Lotus Salvus for a couple of days?"

Caleb pulled the car back onto the road. "I can escape from the Institute; that isn't a problem. Your friends aren't going to mind me invading?"

"They were the one who chose to reveal themselves to begin with."

Caleb looked at the clock on the dashboard, loudly proclaiming that it was after 3 in the morning. "Then...Let's get some sleep at my house, and we can leave for the mountains in a few hours. Unless you think your friends won't be safe in my neighborhood. You were in a hurry to get out the morning you arrived."

Luke shook his head. "I was only nervous about concealing the turtles from you. They're good at disappearing, Caleb. I think they can handle one night at your house."

Caleb nodded. "All right. We'll take this one step at a time...and figure out where to go from here."

"You don't have to feel obligated," Luke told him. "They're not your problem, and if you decide you don't want anything to do with this...All you have to say is that the research isn't complete, and it can't be done this quickly. You don't have to give them or me any more reason than that."

Caleb's brow furrowed as he gave the younger man another quick glance. He's trying so hard to give me a way out, even though I don't think he wants me to take it. How does anyone live this way? The constant hiding, the stress...I can't imagine how it must affect him. I suppose it can drive someone to break into a Genetic Institute without a backup plan, he thought sardonically. I have a feeling I don't know what I'm walking into. I hope I'm not making a huge mistake.